Does A UV Water Disinfection Plant Opening In New York Mean More Chlorine Added To Drinking Water?

New York will be opening the world's largest ultraviolet, or UV, drinking-water disinfection plant in a couple of months, Scientific American reported Friday.

The facility will have 56 enormous UV units that will neutralize waterborne pathogens in all the drinking water that comes from the Delaware County and Catskill watersheds, the site said.

A reported 9 billion liters of water will be processed a day -- and a second layer of sanitation to the chlorine treatment will have been added -- according to Scientific American.

The Delaware County and Catskill watersheds have not been required to have such disinfection in the past. Because of stricter regulations promulgated by the U.S. Environmental Protection Agency, or EPA, in recent years, however, the city has been coaxed into ensuring that its drinking water is safe.

The disinfection facility reportedly cost $1.6 billion to build. It is located in Greenburgh and Mount Pleasant in Westchester County.

The official date for the facility to go live is Oct. 29, Scientific American reported.

Instead of adding more chlorine to the drinking water, UV lights will alter the DNA of cryptosporidium, giardia, and other waterborne pathogens so they can't reproduce, the site said.

If people were to ingest such waterborne pathogens, they could suffer from nausea, diarrhea, cramps, or other serious symptoms.

The EPA began to require that unfiltered surface-water treatment systems -- like the one responsible for New York's drinking water -- filter drinking water or use something other than chlorine to get rid of the microorganisms in 2006, Scientific American wrote.

More chlorine won't be added to the water since the plant uses UV technology, in addition to chlorine.

Using two methods to kill pathogens in drinking water is necessary because cryptosporidium can pass through chlorine but not UV disinfection, while adenovirus is resistant to UV disinfection but not chlorine.

Even though adenovirus is not typically found in water reservoirs, there is still a risk of it entering the water system because of increased development, the University of North Carolina at Chapel Hill's Mark Sobsey told Scientific American. Sobsey is a professor of environmental sciences and engineering, and the director of the school's Environmental Microbiology Laboratory.

"We have to assume that there is some risk of adenoviruses getting into these water sources from human fecal contamination, such as septic tank effluents that may discharge into some waters and eventually enter the reservoirs," Sobsey said.